Restaurants and other food preparers and servers have long required simple means for heating or maintaining foods at an elevated temperature for extended periods of time. The need has been particularly strong for buffet service or for table service where some items are kept hot at the table. However, such heating means have been subject to criticism as fires start and spread when they are tipped over. There has been a need for a liquid fuel burner that has a spill proof design.
Canisters containing jellied fuels, under the name CANNED HEAT, have been in use for many years. CANNED HEAT is the registered trademark of CPL Industries. Canisters with liquid fuels are also used. At first volatile alcohol fuels were used, but more recently fuels of low volatility, such as glycols, have come into use. The usual liquid fuel burner has a wick which concentrates the flame into a small area. There has been a need for a fuel burner having a construction which spreads the flame over a substantial area for a less concentrated application of heat, and for a fuel burner that will not spill its fuel in cases of accidental tip-over.
Devon--U.S. Pat. No. 3,888,620--discloses a canned burner using a wax fuel and having a tubular wick which protrudes above the can at several points.
Huber--U.S. Pat. No. 3,262,290--discloses a canned burner using a liquid fuel and a wick stone.
De la Rosa--U.S. Pat. No. 4,604,053--discloses a canned burner using a liquid fuel and having a flat wick which protrudes above the can through an opening so that the middle portion of the wick is exposed and the ends are positioned in the liquid fuel.
Bandel--U.S. Pat. No. 4,624,633--discloses a canned burner using a liquid fuel and having a central wick which protrudes above the can through a center opening. Glycol fuels are claimed as the novel feature.
Menter--U.S. Pat. No. 4,611,986--discloses a canned burner using a liquid fuel and having a central flat folded wick which protrudes above the can through a center opening.
Norwegian Patent No. 59,224 and British Patent No. 845,639 disclose liquid fuel burners with special wick constructions.
The present invention relates to a fuel burner capable of retaining its liquid fuel therein in case of accidental tip-over, which prevents the spread of fire. In particular, the present invention relates to container having a closed bottom, an enclosing side wall and an open top, at least partially filled with a layer of fibrous material, at least partially saturated in a liquid fuel, which fibrous layer can officially transmit the liquid fuel to the burning surface at the top opening of the container, but which fibrous layer will significantly impede the flow of liquid in response to gravitation, such as in an accidental tip-over.
Present invention also relates to a fuel burner capable of supporting combustion above a liquid fuel soaked fibrous material, which material will not itself burn, at least not while liquid fuel is still being consumed.
The present invention is also distinguished from this and other prior art by a disposable fuel burner which comprises a container having a closed bottom, an enclosing sidewall and an open top and at least partially filled with a fuel. A support member is supported adjacent the open top above the fuel and having a centrally located opening receiving one end of an elongated wick of a fibrous material, e.g., cotton or glass fibers, overlying the support member and having its other end immersed in the fuel. The support member may be flat and made of a cardboard or plastic disk supported on legs or a cylinder or may be a cup-shaped member. A fibrous layer is located on the support member and is capable of retaining fuel therein and capable of supporting combustion at the surface thereof while also being able to contain such liquid or jellied fuel in the event of an accidental tip-over substantially fills the container. In the alternative, a non-combustible material, e.g., glass fibers, substantially fills the open top and overlies the support member and the end of the wick supported thereon. A layer of a plastic, e.g., polyurethane, foam material overlies the fibrous layer. A top cover is secured on the container closing the open top and is at least partially removable, e.g., removable cover or pull-tab opening cover, to expose the layer of plastic foam, whereby the burner may be ignited with the flame extending substantially uniformly from said entire top opening and continuing to burn until extinguished or said fuel is exhausted. The plastic foam layer is combustible and burns off in use with the flame being subsequently emitted from the surface of said fibrous layer.